Field of the Invention
The present invention relates to a vehicle lighting device equipped with a light deflector that scans light beams.
Description of the Related Art
As a vehicle lighting device to be mounted on a vehicle, there is one adapted to scan a light beam from a light source, such as a laser, by a light deflector, such as a microelectromechanical system (MEMS), draw a two-dimensional image on a fluorescent screen, and project at front the two-dimensional image in the form of a light distribution pattern. A single light source cannot provide a sufficient amount of light required of such a vehicle lighting device, so that a plurality of light sources are used.
For example, according to the vehicle lighting device described in Japanese Patent No. 4881255, light beams are emitted from three light sources to different parts of a light-deflecting mirror of a light deflector, and the light-deflecting mirror is rotated in this state to perform scanning, thereby forming three light distribution patterns. Then, the three light distribution patterns are partly overlapped to provide a desirable light distribution pattern obtained from the vehicle lighting device, in which the intensity of light is high at a center and low at an edge portion.
However, according to the vehicle lighting device described in Japanese Patent No. 4881255, the light beams from the three light sources are directed to different parts of the light-deflecting mirror, so that the size of the light-deflecting mirror has to be increased, as compared with a type adapted to emit a light beam from a single light source to a single light-deflecting mirror. If the light-deflecting mirror is made larger, then the motion thereof will be slower, thus it is not possible to obtain a higher resolution of the projected light distribution pattern.